Signaling device



P 3, 1940- P. J. YGILINSONY 2,213,493

S IGNALING DEVICE Filed Oct. 5. 1936 Patented Sept. 3, 1940 1? A'TENT' POJFFICE SIGNALING DEVICE Philip J.. Gilinson. Lowell, Mass, assi'gnor to Heinze Electric; Company, Lowell, Mass, a.- corporation of Maine Applicationoctober 3, 1936, SerialNo. 103,842

1 Claim." (01. 177-7) This invention relates to improved electric signaling devices on horns of the type wherein a diaphragm is vibrated by'electromagnetic means energized, for example, through a make-and- 5 break mechanism. The present invention more particularly provides an especially advantageous arrangement of the magnetic assembly permitting efiicient operation of the horn to give a relatively loud sound in response to energization by "a 1'0 moderate electric current. The arrangement also permits inexpensive manufacture and assembly sothat especial careand accuracy is not required in order to have the parts of the horn operate efficiently.

To permit these desirable results the magnetic assembly preferably partakes of the character-' istics of both a conventional electromagnet and of a solenoid. Thusga-magnetic coil is provided with a coremember disposed in one end. A plunger connected'to the vibratory diaphragm extends into the other end of the coil an'd has; an end juxtaposed to the end of the core member. Accordingly when the coil is energized the plunger is drawn toward the core member both'due to the attraction of the plunger to the coil and the attraction of the plunger to the core member. Such an arrangement avoids a tendency-toward tilting which may sometimes occur with the conventional;

armature type magnet, when associated with an armature at the center of a relatively large diametered' flexible diaphragm. Such tilting ofthe armature and the central portion of'the diaphragm results in-an uneven vibratory action and a loss in operating efiiciency,'and injmany cases also results in a disagreeable note: "The arrangement of-the' plunger in'the manner permitted' by this invention permits theamplitude of vibration of'thecenter of the diaphragm to be relatively large, since the plunger may have 40 a relatively'long path of movement due to; the

solenoid-action,"and since the core member afiords-anincreasing attraction for the plunger at the inner end of "its path. Thus at the beginning of the inward movement of the'plunger a substantial 'fraction of the total attracting "force comes directly from the coil itself, but, as the resistance to further'distortionof the diaphragm increases, the end of the plungerapproaches the end'ofthe core'member and the'latter becomes increasingly efiective in .attracting"the plunger. 'I'lresolenoidefiectresults in proper centering of the plunger so that tilting of the diaphragm is avoided and it may have the full desired amplitude of movement without objectionable dis- 5; tortion.

Further features of the invention 'relate' the arrangement of the component parts'of theassembly to permit inexpensivemanufacture of an efiicient warning signal. I

In the accompanying drawing I Fig.1 is a broken sectional view'of a signaling device constructed inaccordance with this in: vention, partsbeing shown in elevation;

Fig. 2 is a sectional detail 'indicatefd'by line 2'2 V of Fig. 1; 10

Fig. 3is anelevational detail of the assembly shown in Fig. 2, parts "being" shown'in section; and

Fig. 4 is a sectionindicated byline 44 of F eis A signaling deviceconstructed in accordance with this invention maycomprise a casing-mem her I of generally cupdikeiormhaving aperipheral flange-2 connected -to'the flange of a front casing'member 3 by fastening means such as bolts 4. The-edge of a metal diaphragm-6 is-secured between the flanges of the casing members-l and 3, as shown in Fig. 1. Asound-duct-H) has a threaded end portion-H received'in an internally threaded boss 12 at the center of thefront casing member 3.

A plunger M is fixed to the intermediate part of thediaphragm' 6. For this pur'pose-a disk'l5 may-be disposed-atthe'front of -the=diaphragm and a stud -l1'mayextendfro'm"th plunger f4 through an opening inthisdisk'and be peened over to secure these parts to the centralfportion of the diaphragm. A' suitable' wire coil' 20 is' disposed about themajor portion of theplunger [4 with the plunger preferably extending substantially'to or} beyond the midpoi'tion of'this coil. Such a coilmay' be convenientlywound'on an insulating assembly intheform of a spool or bobbin 22. The latter is secured, in-"a manner pres'ently'to be-described-, to 'thecentral'portion of the-rear casing member "I so -'-that-the coil is 40 fixedly mounted on'this casing member.

A-"core member -23 is secured'tothe center of the casing I and extends into the rear part-of the coil, having an end face spaced from the inner end of the plunger 14, asshown'in Fig. 1. 'The core member "23 is normally ifixed, but may be adjustable to permit conveni'entadjustment of the horn fromth'e exterior thereof. For this purpose a reinforcing disk 26 is "welded to the outer ia'ceof the central portion of the "casing member I, and is provided with a threaded opening to receive a stud 21 extending rearwardly from the core member 23. The end of the stud 21 is slotted as designated by numeral 28 to receive the end of a screw driver, and the stud engages a locking nut 29 which normally is held against the outer face of the disk 26. When it is desired to adjust the member 23, the stud 2'! is held against rotation by a screw driver, and the nut 29 is loosened, permitting the stud to be screwed inwardly or outwardly, thus allowing the spacing of the plunger and core member to be varied. When the desired setting of the core member has been attained, the nut 29 is tightened to hold the assembly in fixed position.

A magnet frame 30 is disposed about the coil 2|], this frame being of generally U-shaped form, as shown in Fig. 2, but having curved legs 3|, Fig. 4, juxtaposed to opposite sides, of -the coil. The bight portion of this member is provided with a central opening 33 through which the plunger l4 extends. The end portions of the legs of this member may be provided with integral extensions 35 which extend through openings in the casing member I and are peened in place so that the frame 30 is permanently secured to the casing. The frame 30 preferably engages the inner end of the'insulating bobbin 22, as shown in Fig. 2, holding the opposite end thereof against the casing, thus being efiective in supporting the bobbin and the wire coil in proper position without the necessity for employing :separate fastening means. Obviously the frame 30 cooperates with the casing, the plunger, the core member. and the coil in aiding the provision of' an efiective magnet circuit.

' The magnetic coil 20 may be energized by any suitable means through a conventional makeand-break mechanism. For example, as shown,

' a. strap metal piece 36 may be clamped between the plunger l4 and the diaphragm 6, this member being L-shaped as viewed in Fig. l and having an end portion engaging the insulating leaf 40 of the make-and-break arm 4|, which carries a movable contact engageable with a fixed contact 42 of the opposite side of the make-andbreak assembly. Arm M is connected by a lead 48 to coil 20 while the opposite end of the coil and the contact 42 are connected respectively to supply leads 5|] and 5|.

Obviously when the circuit is closed between the supply leads 50 and 5|, current is supplied to the coil 20 and the plunger i4 is drawn rearwardly. Thus a relatively long vibratory path is imposed upon the diaphragm, while the centering action of the coil upon the plunger prevents tilting of the diaphragm so that the device tends to be automatically self-centering and especial care in assembly is not necessary. Furthermore, the space betweenthe plunger I4 and the wall of the opening 33 in the magnet frame 30 affords a definite air gap of uniform non-changing size in the magnet circuit. Such an air gap is advantageous in avoiding the lag in the movement a of the diaphragm which occurs in many conventional horns at the end of the inward movement of the armature toward the magnet due to the extremely minute air gap which may then be provided in such horns. Obviously when the plunger 14 closely approaches the core member 23 the part 36 is effective in separating the contacts so that the electrical circuit is broken and thediaphra'gm moves back toward its normal position, whereupon the contacts again engage and the vibratory movement is repeated.

The make-and-break mechanism obviously may be adjustable in any suitable manner, for example, the arm 4| or the opposite arm of the make-and-break mechanism may be bent slightly to vary the point in the vibratory path of the diaphragm at which the contacts are separated. Moreover, it is obvious that known arrangements of the make-and-break mechanism may be provided so that the same may be adjustable from the outside of the casing; the example, one arm of the mechanism might be made adjustable through a suitable insulated screw extending through the wall of the casing.

A very effective adjustment is provided, however, by the arrangement of the plunger and core member so that the space between the ends of the same may be varied from the exterior of the horn. Such an adjustment permits the spacing of their parts to be varied until the maximum volume is attained at the position of adjustment wherein the plunger very closely approaches the core member at the inner end of its stroke. Obviously the principles of this invention may be employed to obtain this advantage if the plunger is adjustably mounted on the diaphragm in the same general manner as the core member is adjustably mounted on the casing in the illustrated form of the invention, but in practice it is preferable to arrange the lighter and smaller core member with an adjustable connection to the fixed casing. Obviously this core member is readily adjusted from the back of the casing either when the horn is being initially tested directly after assembling, or when the horn is actually in operation on a vehicle or the like. This adjustment requires only the movement of the small core member 23, While the magnetic coil 20 remains permanently fixed to the casing, thus affording an unusually sturdy arrangement which is not likely to loosen when subjected to vibration.

It is evident that the arrangement disclosed herein permits a signaling device of the type described to be manufactured and assembled at very low cost, while affording a device which provides a clear tone that has previously only characterized more expensive devices with more elaborate assemblies which were more likely to get out of order.

It should be understood that the present disclosure is for the purpose of illustration only and that this invention includes all modifications and equivalents which fall within the scope of the appended claim.

I claim:

In an electric horn of the vibrator type, a solenoid, a first member extending across and in contact with one end of said solenoid, and a second member extending across and in contact with the other end of said solenoid and along the sides of said solenoid and secured to said first member and being generally of a U-shape, said members forming both a means for clamping said solenoid tightly in a fixed position and a path for'lines of magnetic flux produced by said solenoid, said U member having the ends of its legs secured by fastening means to said first member for holding the solenoid in place and for securing the members together in a common magnetic circuit.

' PHILIP J. GILINSONp 

